UPDATE AS OF 11:30 A.M. EDT, TUESDAY, APRIL 12
Tokyo Electric Power Co. (TEPCO) is planning to pump highly radioactive water from reactor 2 into a condenser, as the utility works to control radiation and restore cooling systems at the Fukushima Daiichi nuclear power plant.
TEPCO continues to inject cooling water into reactors 1, 2 and 3 and to spray water into the used fuel pools for reactors 1-4. TEPCO also continues injection of nitrogen gas into the containment vessel of reactor 1 to prevent a possible explosion of hydrogen that may be accumulating inside.
A fire that broke out early Tuesday at a distribution switchboard near the south water discharge channel for reactors 1-4 was extinguished without interruption of reactor cooling operations or the release of radioactivity, TEPCO said.
The crisis rating of the Fukushima Daiichi accident was raised from 5 to 7 on the seven-level International Nuclear and Radiological Event Scale by the Japan Nuclear and Industrial Safety Agency. The new level, the highest on the scale, designates Fukushima as a “major accident.” The new rating puts the Japanese incident on the same level as the 1986 Chernobyl accident—even though Japanese authorities estimate that radiation released at Fukushima is only 10 percent of the amount released from the Ukrainian plant.
Authorities said much of the high-level radiation leaked from reactor 2 on March 15 and 16, early in the accident. Abnormalities in the reactor’s suppression pool caused the radiation release, the Japan Nuclear Safety Commission said. Radiation continues to leak from the suppression pool, the commission said, but the volume has dropped considerably.